Sputtering, physical compounds

R. Behrisch, ed., "Sputtering by Particle Bombardment II Sputtering of Alloys and Compound, Electron and Neutron Sputtering, Surface Topography," in Topics in Applied Physics, Vol. 52, Springer-Vedag, Berlin, 1983. 

The hybridizing component can also be formed directly on the surface of a pristine or modified nanocarbon using molecular precursors, such as organic monomers, metal salts or metal organic complexes. Depending on the desired compound, in situ deposition can be carried out either in solution, such as via direct network formation via in situ polymerization, chemical reduction, electro- or electroless deposition, and sol-gel processes, or from the gas phase using chemical deposition (i.e. CVD or ALD) or physical deposition (i.e. laser ablation, electron beam deposition, thermal evaporation, or sputtering). 

Among the physical techniques, reactive sputtering is used most frequently because it produces films of high purity with relative ease and good reproducibility. In addition, many compound types can be prepared (carbides, nitrides, oxides, carbonitrides, oxicarbonitrides) including metastable phases. 

It is a remarkable feature of secondary ion mass spectrometry (SIMS) that considerable chemical information is accessible through the procedurally simple physical technique of sputtering. SIMS--espec ia 11 y under low primary ion flux conditions ("static SIMS," a 1 s o known as "molecular SIMS" when applied to compounds)—provides information on molecular weight and molecular structure and allows isotopic analysis. The surface sensitivity of SIMS permits its use in imaging, in monitoring of surface... 

Christner et al. (1979) have prepared their samples by dc sputtering and described their experimental procedure in detail. They have minimized the contamination by oxygen which can influence the physical properties. The X-ray diffraction patterns show the formation of the ErRli4B4 compound and a small amount of RhB. The composition has been also studied by AES. The superconducting transition temperature varies from 6.0 to 7.8 K, which is somewhat different from the bulk (8.7 K). One film exhibits such a temperature and returned to the normal state at about 1.0 K (in the bulk state the change to the magnetic state is 0.9 K). Another sample, exhibiting the presence of RhB, has a transition temperature of 4.5 K. 

A vacuum technique closely related to CVD is PVD (physical vapor deposition), in which a solid (metal or compound) is evaporated in a vacuum by heating or by a plasma (called sputtering) and condensed on a substrate to form a coating. Often there is no chemical reaction during deposition—hence the name. PVD is a line-of-sight process, and unlike CVD it suffers from shadowing on profiled surfaces if the substrates are stationary with respect to the source. 

Physical vapor deposition (PVD) is a technique for making thin films at low temperatures and is widely used in planar technology in electronics. It consists of evaporating or sputtering a solid, such as a metal, an alloy, or a mixture of solids, in a vacuum and condensing the compound on the substrate to be covered. In certain variations the vapor is reacted with gases introduced in the vacuum. That variation is reactive evaporation or reactive sputtering. The product can be a polycrystalline deposit or a powder. 

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